package simpledb.storage;

public class ListNode {
    public ListNode pre;
    public ListNode next;
    public PageId pageID;
    public ListNode(){
        this.pre=null;
        this.next=null;
        this.pageID=null;
    }
    public ListNode(PageId PageID){
        this.pageID=PageID;
        this.next=null;
        this.pre=null;
    }

}
